Cutie and the Boxer is a biographical documentary about art, culture and marriage. The opening credits show famed Japanese boxer painter Ushio Shinohara in action, using his paint-drenched boxing gloves to punch out another art work. The 81-year-old Shinohara returns to dip the attached sponges in black paint, shielding his eyes from splotches in a signature style that he could have done more than a thousand times.

Shinohara is surely the most famous of struggling New York artists, having achieved acclaim in art circles at various points in his career for his boxing style and monstrous motorcycles, creating the sort of expressive art that people rarely buy for their homes. He's seen it all, having created an art niche for himself in New York City, yet battling the stresses of inconsistent sales and hard living.

Yet, this story isn't only about Ushio, it's also about his wife, Noriko. Their chaotic 40 year marriage becomes the focus of this fascinating documentary by writer-director Zachary Heinzerling. Ushio's led an unappreciated art career, earning the historic interest of the Guggenheim and art dealers, yet struggling to pay the bills. His loyal wife has played assistant to the great artist, putting her own artistic ambitions on hold to assist, manage and take care of the teacher and resident genius.

Naturally, this environment is tense, tempered by bittersweet humour and nostalgia. Heinzerling captures the story so far... and then explores Noriko's new-found inspiration as the "apprentice" develops her biographical art. Noriko's brutally honest art helps us understand their relationship, relaying the story of a domineering husband in the throes of self doubt and a subserviant wife and dormant talent.

Heinzerling has an intimate perspective on the Shinoharas, exploring their history, their art, their home and their studio. He captures beautiful moments and real emotion in the frank exchanges between Ushio and Noriko, who behave like no one's watching. Noriko's work fills in some of the gaps as Heinzerling animates it to tell us part of the untold family story. It's warts-and-all love between two artists with a growing competitiveness that plays out in Cutie and the Boxer.

Just like Exit Through the Gift Shop, there's a similar raw intensity, rebellious spirit and grungy street art feel to the Oscar-nominated Cutie and the Boxer. It's a tour of the modern art world, it's a sign of the times, it's a chronicle of a strained marriage and it's a colourful ode to the ceaseless passion that drew and kept two people together.